Bolt-anchor.



T. F. KELLER.

BOLT ANCHOR.

APPLICATION FILED JUNE 21, 191s.

1,1 16,71 0.. Patented Nov. l10, 1914.

WITNESS/SS:

' ATTORNEY llhllTEU STATES PATENT. OFFICE.

JRUGOTT 11, KELLER, U1? BROR'LYN, NEW YORK, ASSIGNR TO THE CLEMENTS COMPANY, .d CUltlPORATION 0F NEW YORK.

BOLT-NCHOR.

To all Iwhom it may concern.'

Be it known that l, lnanoo'r'r l41 KELLER, 'a citizen ot the United States, and a resident of Brooklyn, in the county of Kings and State of New York. have invented certain new and useful improvements in Boltnchors, of which the following is a specitication, reference being had to the accompanying drawings, forming a part thereot.

My invention relates to improvements in bolt anchors and its object is to provide a simple and inexpensive device of this character which shall have advantages over those which hitherto have been known.

ll. will describe my invention in the tollowing specification and point out the novel tea-tures thereof in appended. claims.

Referring to the drawings,ld`igure 1 is a sectional elevation ot a wall with a bolt anchor therein which embodies the present invention, together with a bolt in the anchor to illustrate the manner in which it is used. Fig. 2. is a sectional side elevation and Fig. 3 is an end View ot the bolt anchor shown in Fig. 1. Fig. fl is an end elevation ot a similar bolt anchor with its nexterior constructed with projections.

lin Figs. 5 and 6 is shown in sectional side elevation and in transverse section respectively, a modified form ot bolt anchor which also embodies my invention, which in this case is made of metal of sutlicient softness to enable the bolt which is used with it, to cut its own thread therein.

Another modication ot construction is shown in Figs. 7 and 8 which are respectively a sectional side elevation and an end view ot a bolt anchor which is solid at its inner end.

Like characters of reference designate corresponding parts in all the ligures.

Bolt anchors constructed according to my invention comprise a cylindrical shell 1() within which is a tapered bore converging toward the inner end ot the shell. 1n the itorms shown in all of the figures except 5 and 6 this tapered bore is provided with screw-threads 11. A longitudinal cut or slit 12 is made through the shell into the bore of the shell which extends-trom the outer end ot the shell back through the greater part of its length. rlhe outside of the shell is substantially cylindrical but it may be cut away as at 18 near the inner end specification of Letters Patent. appli-canoa inea .rune 21,1913. serial Nc. maar.

place.

Patented Nov. 10, 191e..

of the slit 12 to make it more flexible at this part. desired it may be provided with projecting lugs such as those shown at 13 1n F 1g. When the shell is made of sott. metal, 1t 1s not necessary to have it internally threaded because the boltvwhich is used with it may cut its own threads in the shell. To facilitate this, the tapered bore may be tluted or provided with internally progectlng longitudinal ribs. Such a shell 1s shown in Figs. 5 and 6 in which it is designated by 10A and the ribs by 14.

'lhe shell 10B shown in Figs. 7 and 8 is slnnlar to that shown in Fig. 2 but its inner end 15 is solid. This shell is shown with two slits 12-12 and it is obvious that one or any' desired number of'these slits may be provided in either this or any ot the other forms.

Referring now to Fig. 1, ll will describe the manner in which this device is used. 1n

a wall, Hoor or other structure 20, a hole 2l 1s drilled oi sutlicient size to permit the insertion of the bolt anchor. Then a bolt 22 is screwed into the tapered thread 12. This causes an expansion of the shell at the outer or slitted end as is clearly illustrated in this Fig. 1. The outer surface of the shell is thus forced snugly against the bore of the hole Q1. and effectively prevents the withdrawal ot the anchor as long as the bolt remains in lf the structure in which the bolt anchor is used is oit' certain materials, it is desirable to provide the exterior ot the shell with the projections 13 in order to increase its holding effect. By slotting the anchor from the outer end, immediate expansion will occur as the bolt enters the anchor. This initial expansion is of great advantage and is accomplished by the bolt engaging the anchor at the outer end. lt is also facilitated by the weakening of the wall as at 18 in Fig. 1.

The arrangement ot' my invention is particularly valuable when the bolt cuts its own threads in the anchor and furthermore perinits the use of bolts of varying lengths. Another advantage arises Ytroni the tact that where a bolt has been used and an anchorage secured, and thereafter it is desired to remove the bolt, another bolt may be used and a new anchorage secured.

l have illustrated several forms of my invention to show that l do not'limit myselit to any specific construction, as many structural modiiications may be made within the spirit of my invention and the limitations of the claims.

What I claim is:

1. A bolt anchor comprising a cylindrical shell adapted to receive an expansion screw and having a tapered hole from the outer end extending through the shell and converging toward the innerend thereof, said shell being slitted longitudinally from its outer end through the greater part of its length.

2. A bolt anchor comprising a cylindrical shell of metal annularly continuous at its inner end having a tapered threaded hole from the outer end converging toward the inner end thereof, said shell being slitted longitudinally from its outer end.

3. A bolt anchor comprising a cylindrical shell of metal annularly continuous at its inner end having a tapered threaded hole from the outer end extending through the shell and converging toward the inner end thereof, said shell being slitted longitudinally from its'outer end through the lgreater part of its length.

4. A bolt anchor comprising a shell having a tapered bore 'converging toward the inner end of the shell, said shell being slitted from its outer end through the greater part of its length and being out away near the inner end of the slit.

5. A bolt anchor comprising a cylindrical shell of hard metal annularly continuous at its inner end, having a tapered threaded hole from its outer end extending through the shell and converging toward the inner end thereof, said shell being slitted longitudinally fromits outer end through the greater part of its length and being provided with ain annular groove near the inner end of the sit.

In witness whereof, I have hereunto set my hand this 19th day of June, 1913.

Witnesses:

I. B. MOORE, M. KRAELER. 

